Purpose and Rationale: This proposal is based upon the premise that a clinically effective cell mediated immune response against spontaneously arising tumors can be elicited by activation of tumor associated antigen (TAA) specific cytotoxic T cells (CTL). Carcinoembryonic antigen (CEA), an oncofetal protein best known for its overexpression in the majority (>90%) of gastrointestinal malignancies, in addition to approximately 50% of lung and breast cancers, is one such TAA. This protocol proposes to examine the safety and feasibility of using a novel form of antigen presentation to induce CTL. Specifically, autologous peripheral blood precursor-derived dendritic cells (DC) will be pulsed with an RNA encoding CEA and administered intravenously to patients with locally advanced or metastatic CEA-expressing malignancies which have been refractory to conventional therapy. Specific Hypothesis To Be Tested: The dose-limiting toxicity and feasibility of administering CEA RNA-pulsed, autologous DC will be defined. As a secondary endpoint, the ability of these CEA RNA-pulsed DC to induce CEA specific cytotoxic T cells will be evaluated. The antitumor effect will also be assessed. Study Design: This open label, uncontrolled dose escalating pilot study proposes a three tiered dose escalation strategy to explore the toxicity of CEA RNA pulsed DC. The highest dose to be tested corresponds to the largest number of DC that can be generated from mononuclear cells harvested from peripheral blood isolated by a routine leukapheresis.